Tracking device for player pianos



April 13 1926. 1,580,240

G. A. FORSBERG ET AL TRACKING DEVICE FOR PLAYER PIANOS 2 Sheets-Sheet 1 Filed May 31, 1924 April 13 1926. 1,580,240

G. A. FQRSBERG' ET AL TRACKING DEVICE FOR PLAYER PIANOS Filed May 31, 1924 2 Sheets-Sheet 2 Patented Apr. 13, 1926.

UNITED STATES ream PATENT orieica.

GUSTAV A. FORSBERG AND THOR W. GRANBERG, OF CHICAGO, ILLINOIS.

TRACKING DEVICE FOR PLAYER PIANOS.

Application filed May 31, 1924. Serial No. 716,913.

To aZZ whom it may concern:

Be it known that we, Gnsrav A. FORSBERG and 'lnoa W. Gnannnae, citizens of the United States, residing at Chicago, in the county of Cook and State of Illinois, having jointly invented certain new and useful Improvements in Tracking Devices for Player Pianos, do hereby declare that the following is a full, clear, and exact description of the same.

In the accompanying drawings. which illustrate a practical embodiment of the several features of our invention, Fig. 1 is a view in front elevation showing the mechanism in playing position and with parts in section at the musicroll chucks; Fig. 2 is a view in front elevation showingthe mechanism in re roll position; Fig. 3 is a view in rear elevation with the parts in the general positions shown in Fig. 2; Fig. at is a detail view on an enlarged scale partly in bottom plan and partly in section taken on the line 1--% in Fig. 3; Fig. 5 is a detail view in rear elevation on an enlarged scale showing certain of the parts in their positions shown in Fig. 1 and Fig. 6 is a fragi'uentary view on an enlarged scale partly in section and partly in elevation.

In the drawings the reference numeral 1 designates the usual spool-box mounted on the shelf 2 in the piano case and in which the take-up spool 3 and the longitudinally slid-able chucks for the removable music or note sheet roll a are journaled. The left roll-chuck comprises a shaft 5 journal'ed in extended bearing 6 on a plate 7 attached to the wall of the box, and is normally pressed inwardly by a spring 8' to revolubly support one of theflanges of the roll 1 and has a collar 9 to limit its inward movement. The right roll-chuck comprises a shaft 10 suitably journaled in the transmission frame 11 attached to the wall of the spool-box and having adjustable inner and outer collars .12 and 13 respectively; the inner end of the collar 12, has means to engage the drive flange of the roll 41' when the latter is inserted between the chucks as shown in Fig. 1 and the outer end of the shaft 10 carries a fixed sprocket 1-1 by which the. roll 4L may be driven to rewind the sheet of music 15 thereon. The take-up spool 3 is adjustable axially by usual suitable means and is revolved by a fixed gear 16 to move the ll'lllSlC Sl'lE6i? 15 over the tracker-bar 1 7 the usual transmission to which motion is imparted from the motor to roll the musicsheet 15 on the spool 3 and re-roll it on its roll 4 is not shown. a

The means for securing the proper tracking or alignment of the music-sheet as it passes over the tracker-bar comprises a lever carrying an edgeguide adjacent an edge of the sheet and pneumatic means controlled by the lever for adjusting the sheet-roll axially of the tracker bar. The control lever 18 is pivoted at 19 near its rear end on a bracket 2-0 fixed on the left-hand wall of the spoolbox in rear of the tracker-bar and carries at its forward free end a finger or edgeguide 21 which overlies the tracker-bar and is adapted to contact with the left-hand edge of the music-sheet. The lever 18 carries near its rear end or pivot a disc-valve 22 which controls the inlet port of a pipe 23 which is mounted at its open end on an angular arm of the bracket and by which atmospheric air is admitted to a port 24: of a tracker bellows or pneumatic 25 which is mounted on a bracket 26 on the box and has a duct 27 connected by a pipe 28 to the suction mechanism, such as the exhaustbellows (not shown). The duct 2? is restricted by a bleedhole 29 to equalize the exhaust of air from the pneumatic 25 with the amount of atmospheric air that normally leaks past the valve 22 into the pipe 23; a clean-out opening giving access to the bleed hole is provided and may be closed bya setscrew 30. A light spring 31 mounted between the spool-box and the lever 18 stresses the lever in its playing or normal position shown in Figs; 1 and 5, which partially closes the valve 22 and abuts the finger 21 on the edge of the sheet .15. T heti'acker pneumatic 25 is mounted vertically with its apex or pivot-ed end uppermost and is expanded by a spring 32; its movable leat 33 carries a fixed vertical arm 34- which projects above and below the leaf, and one end of a horizontal rod 35 is adjustably connected to the upper end of this arm by opposite nuts 36 threaded thereon; the other end of the rod 35 is pivoted to the upper end or" a lever 37 fulcrumed at its lower end at 38 on a bracket 39 carried by the transmissionframe 11 on the spool-box. The lever 37 abuts against the right-hand end of the sliding shaft 10 of the music-roll, and it is apparent that theie parts are in pneumaticbalanceand as the pneumatic 25 is collapsed more or less the" sheet-roll 4; will be moved to expand the sheet-roll will be moved to the right under the st-res'; of the spring 8.

In assemblin the arts the ole in or 4 to normal position oi the linger 2;. is taken as a guide or gauge and such initial adjustments of parts are made as 'will eniure proper alignment of the sheet with the trachenbar when its edge is against the finger. it in the playing 01' the instrument the sheet moves to the left out of proper alignment with the tracker-bar the valve 22 will be moved by the finger 21 to open or enlarge the port of pipe to the atinospheric air, and as this intake of air is new larger than the amount sucked through the bleedhole 29 the pneumatic 25 will expand under the action of its spring ano move the music-roll to the right to its proper traching position. l t the sheet moves to the right out of proper alignment, the linger "31 is free to follow it a d the valve 22 under the pressure of its spring 31 will move to close or restrict the port of the pine 23 to correspondingly cut-oft the supply of air to the pneumatic 25 which causes the latter to collapse and move the music roll to the left. In either case the sheet is restored to proper alignment with the tracker-bar.

m1 '-devices uch as ine operation of tracl'in herein described is reatly la i i note sheet is correctly row un as then the subsequ "l when it again inseted in will be more accurate. t 7 vice functions during the playing or composition and secures correct lateral adjustment of the sheet on the traclzer-bar the music-roll is usually in proper alignment with the take-up spool when sheet is finished. Butin rewinding" the sheet the exhaust is cut ell from the pneumatic 25, and as the tracking-device is then unbalanced and inactive the music-roll is torced to the rightby its spring and it the sheetis then rewound it will be unevenly rewound thereon. One of the features of our invention is the provision of pneumatically controlled means whereby the music-roll i is locized'in c rrect ali nent with the tracker-bar and take-up spool when the playing of a note sheet is finished and is held in that final position during the rewindingof the sheet, so that the sheet will be evenly rewound on its roll. I so, in rewinding' the note sheet on its roll it is devirahle to withdraw the control-finger 2i of the trackingdevice from contact with its edge, and one of the atures of our invention is the provision pneun'iatically controlled means to accomplish this purpose.

In the preferred embodiment of our invention a single pneumatic contro led by the main exhaust operates means during the reauxiliary bellows or pneumatic ll winning operation to hold the tracking-device in position to align the music-roll with the take-up spool, and also means to move the control-finger away from the edge of the sheet. As here shown the fixed leaf of the pneumatic'25 carries the fixed leai l0 of an iaving an eIpanding spring 42; a duct l3 (Fig. 6) leading through the fixed leaves of both pneumatics into the duct 2'? establishes communication with exhaust pipe 28. The pneumatic ll is mounted with its apex or pivoted end lowermost, and its movable-leaf ll carries at its free end a lined wing; 45 in which one end of a rod l6 is adjustably held byopposite nuts l? threaded thereon; the free end oi the rod passes freely through a guide 4-8 integral with the bracket 2-0 and abuts against the outer end of a rearwardly projecting tail of the lever 18 when the pneumatic ll is xpanded and moves the linger 21 away from the edge of the sheet 15, and when the pneumatic ll is collapsed the rod is withdrawn from the tail to permit the spring 31 to move'the finger into its normal position in contact with the sheet. By pivoting the control-lever 18 at the rear ot the spool-box and mounting the valve on the lever near its pivot the leverage provided by the distance from the pivot to the control-linger 2i al'lords sullicient power to allow the latter to move the valve easily and readily under sight stress of the sheet, so that any danger of valve-sticking; is obviated. Also, the leverage provided. by t tail 119 of iifi the valve is so great that a slight movement of the rod 16 will be 5 i quickly open the valve and ithdraw l linger 21 from contact with the sheet. The movable leaf carries at its pivoted end an outwardly projecting; arm to one side 0'' which the inner end oil a ratchet-bar :l flexibly pivoted at the free end of t bar projecting outwarcly into the plane or an inwardly facing pawl 53 formed on the lower end of the arm Ell on the mo b'o lent ot the pneumatic 25 The outer end or the arm 50 is formed with a beveled lip El which overlies a lateral pin 55 on the ratchetbar, and aspring 56 mounted on the tired leaf l0 holds the pin against the lip when the pneuniiatic ll is collapsed, the bar bein then rocked down out of the path of the pawl by the lip 5a engaging the pin as shown in p The inner face of the pawl and. the outer end of the bar are oppositely beveled so that the pawl may readily back onto the bar in case the expansion of the pneumatic 25 carries the pawl beyond the outer end of the bar; the pin 55 engaging the lip 54: prevents the bar from rising beyond the range of thee beveled portions.

When a note sheet is positioned and the exhaust apparatus is operated for playing purposes the auxiliary pneumatic 41 is held collapsed by the suction through the pipe 28, and the finger-operating rod 46 and the ratchet-bar 51 occupy their inoperative positions as shown in Fig. at the playing only the tracking-device operates as above described. lVhen the playing of a sheet is finished the tracking-device remains temporarily in balance with the sheet in alignment with the tracker-bar and the music-roll ap proximately in alignment with the take-up spool. hen the sheet-rerolling mechanism is operated the suction or exhaust is cut-oil from the pipe 28 in the usual way, and the pneumatic l-l expands under the action of its spring 42. During the initial expansion of the pneumatic 41 the rack 5-1 engages the pawl 53 to hold the pneumatic against further expansion and preserve the trackingdevice in balance in the final position it oeeupied when the playing of the sheet was finished, whereby the sheet is aligned with the tracker-bar and the music-roll is held in substantial alignment with the take-up spool for proper rewinding of the sheet. The rack 51 when operated can engage the pawl 53 in any position of the tracker-pneumatic 25 in its entire working range, and when the playing of a roll is finished the trackerpneuinatic and the tracking-device are automatically locked in the final positions they then occupy. The flexible joint of the rackbar allows the pawl to remain in engagement with the bar and preserve the pneumatic 25 in fixed position and the tracking-device in balance while the pneumatic 41 further expands as shown in Figs. 2 and 3, and when the pneumatic 41 is sufficiently expanded the rod 46 engages the tail of the controllerer 18 and moves the finger 21 away from the edge of the sheet. The interlocking of the auxiliary pneumatic 41 and the tracking-device pneumatic 25 holds the latter in fixed position during the rewinding of the sheet on its roll and prevents it from expanding and destroying the lineup of the music-roll and take-up spool. This interlocking occurs automatically and in timed relation, and the withdrawal of the finger 21 from the edge of the sheet is'rproperly timed by the adjustment of the rod 46. Atter the sheet is rewound on its roll and removed. from the chucks the parts return to their normal positions shown in Figs. 1 and 5 to receive another music roll.

lVe claim:

1, A tracking mechanism for player pianos including a tracker bellows having a port and operative during piano playing, means operatively connected to the movable leaf of said bellows for efiecting adjustment of a music-roll in relation to a tracker-bar, a tracking-controller co-operating with said port and with an edge of a music-sheet on the roll, an auxiliary bellows operative dur ing the rewinding of the sheet on its roll,

and means controlled by the. auxiliary bellows and operative at the completion of the playing of a, sheet-to lock the tracker bellows in the position it then occupies.

2. A tracking mechanism for player pianos including a tracker bellows.- having a port and. operative during piano playing, means operatively connected to the movable leaf of said bellows for effecting adjustment of a music-roll in relation to a trackerbar, a tracking-controller co-operating with said port and with an edge of a music-sheet on the roll, an auxiliary bellows operative during the rewinding of the sheet on the roll, and a ratchet mechanism controlled by said auxiliary bellows to hold said tracker bellows from expanding during such rewindi-ng beyond the position it occupies when the playingof a sheet is finished.

3. A tracking mechanism for player pianos including a bellows having a port and operative during piano playing, means operatively connected to the movable leaf of said bellows for effecting adjustment of a music-roll in relation to a tracker-bar, a tracking-controller co-operating with said port and with an edge of. a music-sheet on the roll, an auxiliary bellows operative during the rewinding of the sheet on the roll, a pawl 011 the movable leaf of said first bellows, and a rack on the movable leaf of said auxiliary bellows constructed to engage said pawl and hold said first bellows, from expanding during such rewinding.

4. A tracking mechanism. for. player pianos including a bellowshaving a port and. operative. during piano playing, means operatively connected to the movable leaf of said bellows for effecting adjustment of a music-roll in relation to a tracker-bar and including an arm having a pawl at one end, a tracking controller co-operating with said port and with an edge of a music-sheet on the roll, an auxiliary bellows operative during the rewinding of the sheet on the roll,

and a rack operated by said auxiliary bellows to engage said pawland hold said first bellows from expanding during such rewinding.

5. A tracking mechanism for player pianos including a bellows having a port and operative during piano playing, means operatively connected to the movable leaf of said bellows for effecting adjustment of a music-roll in relation to a tracker-bar, a tracking-control finger pivoted in the rear of the spool-box and co-operating with said port and with an edge of a music-sheet on the roll, an auxiliary bellows operative during the rewinding of the sheet on the roll, a rearwardly extending tail on said finger and a rod operated by said auxiliary bellows to contact with said tail to withdraw said finger from the edge of the sheet during such rewinding.

6. A tracking mechanism for playerpianos including a tracking bellows, means operatively connected to the movable leaf oi said bellows for effecting adjustment oi a music-roll in relation to a tracker-bar, a pawl on the movable leaf of said bellows, an auxiliary bellows operative during the rewineing of the sheet, and a spring-pressed rack pivoted on said auxiliary bellows to engage said pawl and hold said tracking bellows in balance during such rewinding.

7. A tracking mechanism for player pianos including a bellows having a port and operative during piano playing, means operatively connected to the movable leaf of said bellows for effecting adjustment of a music-roll in relation to a tracker-bar and including an arm having a pawl at one end, a tracking-controller co-operating; with said port and with an edge of a music-sheet 011 the roll, an auxiliary bellows operative during the rewinding of the sheet on the roll, a rack flexibly mounted on the movable leaf of said auxiliary bellows to engage said pawl and hold said first bellows in balance during such rewinding, and means operated by said auxiliary bellows to withdraw said controller from the edge of the sheet,

8. A tracking mechanism "for player pianos including a bellows having a port and operative during piano playing, means operatively connected to the movable leaf of said bellows for efi'ecting adjustment of the Lesseeo sheet on the roll, an auxilia y bellows operative during the rewinding off the sheet on the roll, racl; flexibly mounted on the movable leaf of said auxiliary bellows to engage said pawl and hold said first bellows in balance during such rewinding, and a rod operated by the movable lean. of said auxiliary bellows to withdraw said finger from the edge of the sheet,

9. In a player piano, the combination of a trackenbar, a music-sheet roll, means including a take-up spool to pass said sheet over said tracker-bar, means acting upon said sheet roll and operative durin the play ing of the instrument to secure correct lateral adjustment of the sheet on the tracker-bar,

and pneumatic means operative at the completion of the playing of the sheet to prcserve the alignment of its roll with the takeup spool in. the position the roll then occopies.

10. In a player piano the combination of an endwise adjustable music-sheet roll, a tracker-bar, means including a take-up spool for passing said sheet over the tracker-lea means operative during the playing of the instrument to laterally adjust said roll in proper alignment with said spool, a bellows operative during the rewinding' of said sheet on its roll, and ratchet mechanism controlled by said bellows to preserve the roll in alignment with the spool.

In testimony whereof we atiix our sign natures.

GUSTAV A. FORSBERG. THOR VJ. GRANBERG. 

